Semiconductor devices, semiconductor packages, and methods of manufacturing the semiconductor devices

1. A semiconductor device comprising: a conductive component on a substrate; a passivation layer on the substrate and including an opening therein, wherein the opening exposes at least a portion of the conductive component; and a pad structure on the passivation layer and in the opening, the pad structure electrically connected to the conductive component, the pad structure comprising: a lower conductive layer conformally extending on an inner sidewall of the opening and on a top surface of the passivation layer around the opening, the lower conductive layer including a conductive barrier layer, a first seed layer, an etch stop layer, and a second seed layer that are sequentially stacked, a first pad layer on the lower conductive layer, the first pad layer at least partially filling the opening, and a second pad layer on the first pad layer, the second pad layer laterally extending beyond the first pad layer to contact a peripheral portion of the lower conductive layer located on the top surface of the passivation layer.

2. The semiconductor device of claim 1 , wherein the second pad layer is directly on a portion of the first seed layer at the peripheral portion of the lower conductive layer, the portion of the first seed layer being located on the top surface of the passivation layer around the opening.

3. The semiconductor device of claim 2 , wherein the first pad layer is directly on the second seed layer and at least partially fills the opening, and wherein the second pad layer is directly on the first pad layer.

4. The semiconductor device of claim 1 , wherein the first pad layer is separated from the first seed layer by portions of the second seed layer and the etch stop layer therebetween, and wherein the peripheral portion of the lower conductive layer is free of the second seed layer and the etch stop layer.

5. The semiconductor device of claim 1 , wherein the lower conductive layer comprises a first portion and a second portion, wherein the first portion surrounds a sidewall of the first pad layer, and the second portion is in contact with the second pad layer and located under the second pad layer, wherein a first thickness of the first portion of the lower conductive layer is greater than a second thickness of the second portion of the lower conductive layer.

6. The semiconductor device of claim 5 , wherein the lower conductive layer further comprises a third portion under the first pad layer and on the top surface of the passivation layer around the opening, and wherein a third thickness of the third portion of the lower conductive layer is greater than the second thickness of the second portion of the lower conductive layer.

7. The semiconductor device of claim 6 , wherein the second portion of the lower conductive layer comprises the conductive barrier layer and the first seed layer that are sequentially stacked on the top surface of the passivation layer, and the third portion of the lower conductive layer comprises the conductive barrier layer, the first seed layer, the etch stop layer, and the second seed layer, which are sequentially stacked on the top surface of the passivation layer.

8. The semiconductor device of claim 6 , wherein the first pad layer comprises a protrusion extending onto the top surface of the passivation layer around the opening, and the third portion of the lower conductive layer is between the protrusion and the passivation layer.

9. The semiconductor device of claim 1 , wherein a top surface of the first pad layer is at a higher level than the top surface of the passivation layer relative to the substrate, and a first bottom surface of a first portion of the second pad layer is at a higher level than a second bottom surface of a second portion of the second pad layer relative to the substrate, wherein the first bottom surface is in contact with the top surface of the first pad layer and the second bottom surface is in contact with a top surface of the first seed layer.

10. The semiconductor device of claim 1 , wherein a top surface of the first pad layer is at a lower level than the top surface of the passivation layer relative to the substrate, and a first bottom surface of a first portion of the second pad layer is at a lower level than a second bottom surface of a second portion of the second pad layer relative to the substrate, wherein the first bottom surface is in contact with the top surface of the first pad layer, and the second bottom surface is in contact with a top surface of the first seed layer.

11. The semiconductor device of claim 1 , wherein the first pad layer comprises copper (Cu), and the second pad layer comprises nickel (Ni).

12. The semiconductor device of claim 1 , wherein the first seed layer and the second seed layer comprise copper (Cu), and the conductive barrier layer and the etch stop layer comprise at least one selected from the group consisting of titanium (Ti), titanium nitride (TiN), tantalum (Ta), and tantalum nitride (TaN).

13. The semiconductor device of claim 1 , wherein the conductive component comprises at least one of a through-substrate via (TSV) penetrating the substrate or a redistribution line electrically connected to the TSV.

14. The semiconductor device of claim 1 , wherein the second pad layer extends on an entire top surface of the first pad layer, the lower conductive layer extends on an entire sidewall and an entire bottom surface of the first pad layer, and the first pad layer is encapsulated by the pad structure.

15. The semiconductor device of claim 1 , wherein a top surface of the second pad layer is substantially planar.

16. A semiconductor package comprising: a first semiconductor chip; and a second semiconductor chip connected to the first semiconductor chip, wherein the second semiconductor chip comprises: a conductive component on a substrate, a passivation layer on the substrate and including an opening therein, the opening exposing at least a portion of the conductive component, and a pad structure on the passivation layer and in the opening, the pad structure electrically connected to the conductive component, the pad structure comprising: a lower conductive layer conformally extending on an inner sidewall of the opening and on a top surface of the passivation layer around the opening, the lower conductive layer including a conductive barrier layer, a first seed layer, an etch stop layer, and a second seed layer that are sequentially stacked, a first pad layer on the lower conductive layer, the first pad layer at least partially filling the opening, and a second pad layer on the first pad layer, the second pad layer in contact with a peripheral portion of the lower conductive layer located on the top surface of the passivation layer.

17. The semiconductor package of claim 16 , wherein the conductive component comprises at least one of a through-substrate via (TSV) penetrating the substrate or a redistribution line electrically connected to the TSV.

18. The semiconductor package of claim 16 , wherein the lower conductive layer comprises a first portion and a second portion, wherein the first portion surrounds a sidewall of the first pad layer, and the second portion is in contact with the second pad layer and located under the second pad layer, wherein a first thickness of the first portion of the lower conductive layer is greater than a second thickness of the second portion of the lower conductive layer.

19. The semiconductor package of claim 16 , wherein the second pad layer is directly on a portion of the first seed layer at the peripheral portion of the lower conductive layer, the portion of the first seed layer being located on the top surface of the passivation layer around the opening, wherein the peripheral portion of the lower conductive layer is free of the second seed layer and the etch stop layer, and the first pad layer is directly on the second seed layer and is separated from the first seed layer thereby.

20. A semiconductor device comprising: a conductive component on a substrate; a passivation layer on the substrate and comprising an opening therein that exposes a portion of the conductive component; and a conductive pad structure on the passivation layer and in the opening, wherein the conductive pad structure comprises: a lower conductive layer on a sidewall of the opening and on a surface of the passivation layer outside the opening, the lower conductive layer comprising a first seed layer, an etch stop layer, and a second seed layer sequentially stacked, a first pad layer directly on the second seed layer in the opening, and a second pad layer directly on the first seed layer outside the opening, wherein the first pad layer is separated from the first seed layer by portions of the second seed layer, the etch stop layer, and/or the second pad layer, and wherein a top surface of the second pad layer is substantially planar.